From: Chris Wilson <chris@chris-wilson.co.uk>
To: Andrew Morton <akpm@linux-foundation.org>,
Matthew Wilcox <willy@infradead.org>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org
Cc: Matthew Wilcox <willy@infradead.org>,
"Kirill A. Shutemov" <kirill@shutemov.name>,
Hugh Dickins <hughd@google.com>, Jan Kara <jack@suse.cz>,
Song Liu <liu.song.a23@gmail.com>
Subject: Re: [PATCH v4] page cache: Store only head pages in i_pages
Date: Sat, 01 Jun 2019 12:44:28 +0100 [thread overview]
Message-ID: <155938946857.22493.6955534794168533151@skylake-alporthouse-com> (raw)
In-Reply-To: <155938118174.22493.11599751119608173366@skylake-alporthouse-com>
Quoting Chris Wilson (2019-06-01 10:26:21)
> Quoting Matthew Wilcox (2019-03-07 15:30:51)
> > Transparent Huge Pages are currently stored in i_pages as pointers to
> > consecutive subpages. This patch changes that to storing consecutive
> > pointers to the head page in preparation for storing huge pages more
> > efficiently in i_pages.
> >
> > Large parts of this are "inspired" by Kirill's patch
> > https://lore.kernel.org/lkml/20170126115819.58875-2-kirill.shutemov@linux.intel.com/
> >
> > Signed-off-by: Matthew Wilcox <willy@infradead.org>
> > Acked-by: Jan Kara <jack@suse.cz>
> > Reviewed-by: Kirill Shutemov <kirill@shutemov.name>
> > Reviewed-and-tested-by: Song Liu <songliubraving@fb.com>
> > Tested-by: William Kucharski <william.kucharski@oracle.com>
> > Reviewed-by: William Kucharski <william.kucharski@oracle.com>
>
> I've bisected some new softlockups under THP mempressure to this patch.
> They are all rcu stalls that look similar to:
> [ 242.645276] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 242.645293] rcu: Tasks blocked on level-0 rcu_node (CPUs 0-3): P828
> [ 242.645301] (detected by 1, t=5252 jiffies, g=55501, q=221)
> [ 242.645307] gem_syslatency R running task 0 828 815 0x00004000
> [ 242.645315] Call Trace:
> [ 242.645326] ? __schedule+0x1a0/0x440
> [ 242.645332] ? preempt_schedule_irq+0x27/0x50
> [ 242.645337] ? apic_timer_interrupt+0xa/0x20
> [ 242.645342] ? xas_load+0x3c/0x80
> [ 242.645347] ? xas_load+0x8/0x80
> [ 242.645353] ? find_get_entry+0x4f/0x130
> [ 242.645358] ? pagecache_get_page+0x2b/0x210
> [ 242.645364] ? lookup_swap_cache+0x42/0x100
> [ 242.645371] ? do_swap_page+0x6f/0x600
> [ 242.645375] ? unmap_region+0xc2/0xe0
> [ 242.645380] ? __handle_mm_fault+0x7a9/0xfa0
> [ 242.645385] ? handle_mm_fault+0xc2/0x1c0
> [ 242.645393] ? __do_page_fault+0x198/0x410
> [ 242.645399] ? page_fault+0x5/0x20
> [ 242.645404] ? page_fault+0x1b/0x20
>
> Any suggestions as to what information you might want?
Perhaps,
[ 76.175502] page:ffffea00098e0000 count:0 mapcount:0 mapping:0000000000000000 index:0x1
[ 76.175525] flags: 0x8000000000000000()
[ 76.175533] raw: 8000000000000000 ffffea0004a7e988 ffffea000445c3c8 0000000000000000
[ 76.175538] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[ 76.175543] page dumped because: VM_BUG_ON_PAGE(entry != page)
[ 76.175560] ------------[ cut here ]------------
[ 76.175564] kernel BUG at mm/swap_state.c:170!
[ 76.175574] invalid opcode: 0000 [#1] PREEMPT SMP
[ 76.175581] CPU: 0 PID: 131 Comm: kswapd0 Tainted: G U 5.1.0+ #247
[ 76.175586] Hardware name: /NUC6CAYB, BIOS AYAPLCEL.86A.0029.2016.1124.1625 11/24/2016
[ 76.175598] RIP: 0010:__delete_from_swap_cache+0x22e/0x340
[ 76.175604] Code: e8 b7 3e fd ff 48 01 1d a8 7e 04 01 48 83 c4 30 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 c7 c6 03 7e bf 81 48 89 c7 e8 92 f8 fd ff <0f> 0b 48 c7 c6 c8 7c bf 81 48 89 df e8 81 f8 fd ff 0f 0b 48 c7 c6
[ 76.175613] RSP: 0000:ffffc900008dba88 EFLAGS: 00010046
[ 76.175619] RAX: 0000000000000032 RBX: ffffea00098e0040 RCX: 0000000000000006
[ 76.175624] RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffffffff81bf6d4c
[ 76.175629] RBP: ffff888265ed8640 R08: 00000000000002c2 R09: 0000000000000000
[ 76.175634] R10: 0000000273a4626d R11: 0000000000000000 R12: 0000000000000001
[ 76.175639] R13: 0000000000000040 R14: 0000000000000000 R15: ffffea00098e0000
[ 76.175645] FS: 0000000000000000(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000
[ 76.175651] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 76.175656] CR2: 00007f24e4399000 CR3: 0000000002c09000 CR4: 00000000001406f0
[ 76.175661] Call Trace:
[ 76.175671] __remove_mapping+0x1c2/0x380
[ 76.175678] shrink_page_list+0x11db/0x1d10
[ 76.175684] shrink_inactive_list+0x14b/0x420
[ 76.175690] shrink_node_memcg+0x20e/0x740
[ 76.175696] shrink_node+0xba/0x420
[ 76.175702] balance_pgdat+0x27d/0x4d0
[ 76.175709] kswapd+0x216/0x300
[ 76.175715] ? wait_woken+0x80/0x80
[ 76.175721] ? balance_pgdat+0x4d0/0x4d0
[ 76.175726] kthread+0x106/0x120
[ 76.175732] ? kthread_create_on_node+0x40/0x40
[ 76.175739] ret_from_fork+0x1f/0x30
[ 76.175745] Modules linked in: i915 intel_gtt drm_kms_helper
[ 76.175754] ---[ end trace 8faf2ec849d50724 ]---
[ 76.206689] RIP: 0010:__delete_from_swap_cache+0x22e/0x340
[ 76.206708] Code: e8 b7 3e fd ff 48 01 1d a8 7e 04 01 48 83 c4 30 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 c7 c6 03 7e bf 81 48 89 c7 e8 92 f8 fd ff <0f> 0b 48 c7 c6 c8 7c bf 81 48 89 df e8 81 f8 fd ff 0f 0b 48 c7 c6
[ 76.206718] RSP: 0000:ffffc900008dba88 EFLAGS: 00010046
[ 76.206723] RAX: 0000000000000032 RBX: ffffea00098e0040 RCX: 0000000000000006
[ 76.206729] RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffffffff81bf6d4c
[ 76.206734] RBP: ffff888265ed8640 R08: 00000000000002c2 R09: 0000000000000000
[ 76.206740] R10: 0000000273a4626d R11: 0000000000000000 R12: 0000000000000001
[ 76.206745] R13: 0000000000000040 R14: 0000000000000000 R15: ffffea00098e0000
[ 76.206750] FS: 0000000000000000(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000
[ 76.206757] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
-Chris
next prev parent reply other threads:[~2019-06-01 11:44 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-07 15:30 [PATCH v4] page cache: Store only head pages in i_pages Matthew Wilcox
2019-06-01 9:26 ` Chris Wilson
2019-06-01 11:44 ` Chris Wilson [this message]
2019-06-02 10:51 ` Matthew Wilcox
2019-06-02 13:11 ` Chris Wilson
2019-06-02 19:28 ` Chris Wilson
2019-06-02 21:47 ` Chris Wilson
2019-06-12 1:46 ` Kirill A. Shutemov
2019-06-12 7:42 ` Chris Wilson
2019-06-19 10:04 ` Chris Wilson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=155938946857.22493.6955534794168533151@skylake-alporthouse-com \
--to=chris@chris-wilson.co.uk \
--cc=akpm@linux-foundation.org \
--cc=hughd@google.com \
--cc=jack@suse.cz \
--cc=kirill@shutemov.name \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=liu.song.a23@gmail.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.